Surfactants play a pivotal role in the manufacturing of microelectronics. For example, during a photolithography process, surfactants are added to photoresist developers to facilitate their distribution across a wafer's surface. Proper distribution of the photoresist developer is crucial to chip configuration. Therefore, a metrology for surfactants is highly desirable. Presently, current microelectronic processes utilize a sonic surface tension measurement as a metrology for surfactant levels. This metrology suffers drawbacks, which includes low sensitivity to changes in surfactant dosages and being operator dependent. A more sensitive metrology and consistent metrology for surfactant levels are thus desired.
Another example of where surfactants are used in a microelectronic process is in the wet-etching stage of wafer manufacturing. Specifically, surfactants facilitate the dispersal of etchants applied to a wafer during an etching process. By doing so, a microelectronics manufacturer can achieve a more uniform and predictable result during the etching process. Precise control of the concentration of surfactant in the etchant can help achieve a more consistent outcome and therefore a need to monitor surfactants added to a microelectronic process is desired.